Have u tried to reset your phone, or remove your icloud account? Your can test it in a Fido store too with another sim.
It's seem a problem with the iPhone not the network.
Have a nice day, it's been a pleasure to assist you today
Hello again @Muniraa,
If your phone is from another carrier it sounds like the SMSC number needs to be updated for Fido.
You can try entering this code in the phone dialer **5005*7672*+1549931123# if that does not work you might have to get the carrier settings updated you can call customer service an ask if they can send the update to your phone.